diff --git a/README_SETUP.md b/README_SETUP.md
index 6a28c66f2dd95483656da8544414d9b43deb88c2..f5a9ab95c89fc7c1c6edbc217a2c3f239425dfd1 100644
--- a/README_SETUP.md
+++ b/README_SETUP.md
@@ -73,5 +73,11 @@ with the then current version of the stored entities.
 ## Unit tests
 
 * We use [MyTAP-1.0](https://hepabolu.github.io/mytap/) for unit tests.
+* Requirements:
+    * mysqladmin
+    * mysqldump
+    * mysql client program
 * Tests are in `tests/test_*.sql`.
 * Run `make test`.
+    * Alternatively, to run the tests in a containerized MariaDB instance, run `make test-docker`,
+      followed by `make test-docker-stop`.
diff --git a/procedures/query/applyBackReference.sql b/procedures/query/applyBackReference.sql
index 1bf1415282599860710219076e7ece49302d5490..2d74f74db8cc43e1b0c54c61d09c75042c2247ab 100644
--- a/procedures/query/applyBackReference.sql
+++ b/procedures/query/applyBackReference.sql
@@ -30,7 +30,7 @@ DELIMITER //
 /**
  * Process a set of entities, keeping those which are referenced in a specific way.
  *
- * This procedure filters a source table and writes the result is written into a target table.  If
+ * This procedure filters a source table and writes the result into a target table.  If
  * the target table is not given, all non-matching entries are deleted from the source table
  * instead.
  *
@@ -58,8 +58,7 @@ DELIMITER //
  * versioned : boolean
  * If True, if a reference is versioned (references to specific versions of entities), the target
  * candidate's version must match.  Therefore, the sourceSet and targetSet must have a `_iversion`
- * column as well (unless sourceSet is the `entities` table).  If `sourceSet` is the `entities`
- * table, unversioned references will result in all versions of a referenced candidate being returned.
+ * column as well (unless sourceSet is the `entities` table).
  *
  */
 CREATE PROCEDURE db_2_0.applyBackReference(in sourceSet VARCHAR(255), targetSet VARCHAR(255),